As the standard of living has been raised and public interest in beauty has increased, the desire to express oneself through cosmetics has also increased. Hair dyeing is an immediate and reliable method for expressing the individuality of oneself and making changes. For this reason, in the modern society, hair dyeing has become popular among people of all ages and both sexes.
In a typical and general of using hair dyes, a dye-containing first agent in the form of cream or lotion is mixed with a second agent containing an oxidizing agent, and the mixture is applied to hair. However, with an increase in the demand for a convenient dyeing method capable of easily dyeing hair by oneself at home, not in a hair shop, foam dyeing is receiving increasing attention.
Foam-type hair dyes are largely divided into an aerosol-type hair dye and a non-aerosol-type hair dye. The aerosol-type hair dye is in a state in which the content is mixed with gas so that the content is discharged by the pressure of the gas. On the other hand, the non-aerosol-type hair dye contains no gas and is configured to form foam when the content passes through a foaming mesh. The aerosol-type hair dye has an advantage in that the content is conveniently used several times, but when it is used in stylish dyeing that requires a large amount of the dye at a time, its efficiency versus the price of the material can be reduced.
Foam-type hair dyes are receiving increasing attention, because they can be easily and conveniently applied to hair even by the user's hand by shampooing the hair. However, the hair dyes also have a disadvantage in that, if the time for which the hair dye is applied to and maintained on hair is long, the content of the hair dye can flow down due to its low viscosity compared to a cream-type product, and for this reason, it is difficult to uniformly dye hair with the hair dye. In addition, the foam-type hair dye has low adhesion to hair, and thus the abilities of the hair dye to dye and decolorize hair are significantly low compared to those of a cream-type product. Further, the foam-type hair dye can cause great damage to hair.
Thus, there is an urgent need for a foam-type dyeing agent, the content of which can be easily and conveniently applied to hair without flowing down and which has excellent dyeing and decolorizing abilities and show minimized damage to hair.
Meanwhile, conventional foam-type hair dyes contain either an anionic surfactant having excellent foam-forming ability or a large amount of an amphoteric surfactant and a polymeric thickener in order to increase the elasticity of foam. However, the use of the anionic surfactant can cause additional irritation or reduce the dyeing ability, and the use of a large amount of the amphoteric surfactant can significantly reduce the dyeing ability compared to the use of the anionic surfactant. In addition, the use of the polymeric thickener enables foam immediately after discharge to be elastic, but there is a problem that, if the foam is allowed to stand on hair for a long time after application, it easily collapses so that the content easily flows down.
In addition, cationic polymers having a significant effect on hair conditioning are not contained in large amounts in the first agent or the second agent in terms of the stability of the content and also show a significant difference in hair conditioning therebetween. Thus, the selection and blending of a conditioning material suitable for a foam formulation are very important.